JP4929935B2 - Magnetic scale body - Google Patents

Description

The present invention is used for position control and position detection of various devices, about the magnetic scale body for suitable position sensor for particular use in adverse environments.

  Conventionally, as an example of the position control technique, there is a slide volume device of a mixer device disclosed in, for example, Japanese Patent No. 2748166 (Patent Document 1). The slide volume device disclosed in Patent Document 1 holds a slider with two guide rails, and moves the slider (a knob and a slide terminal) with a drive motor. An operation amount (for example, a voltage value) corresponding to the position of the slider is detected by a slide terminal attached to the slider and a resistance unit in contact with the slide terminal. The position of the slider is controlled by the rotation of the drive motor. Such control of the rotational position of the drive motor depends on the amount of rotation of the drive motor itself.

  In such a slide volume device, the slider is required to move smoothly for both automatic driving and manual driving by a motor, and accuracy of position control of the slider is required. That is, for long-term use, guide performance, durability of the guide structure, and durability in accuracy are required. However, since the guide-dedicated configuration called the guide rail, the configuration that detects the slider operation amount such as the slide terminal and the resistance unit, and the configuration of the slider position control that controls the rotation amount of the drive motor are separated, the apparatus is Complex and expensive.

  In addition, it is difficult to maintain both the structure of holding the slider with the guide rail and the structure of bringing the slide terminal into contact with the resistance unit with accuracy over a long period of time. Further, if it is attempted to maintain the accuracy of both of these structures, restrictions such as the clearance between the guide rail and the slider become strict, and the smooth operation of the slider becomes difficult.

  In contrast, the present applicant has developed a technique for directly detecting the position of a slider (operator) in a slide volume device using a magnetic scale body and a magnetic sensor, and has applied for a patent (Japanese Patent Application No. 2005-195236). ). In this technique, a round bar-shaped main moving guide body and a sub-moving guide body constitute a moving guide portion composed of two parallel strips, and a moving block having an operator and a magnetic sensor is slid on both moving guide bodies. It is held freely. Further, the sub-moving guide body is a magnetic scale body, and is composed of a substantially round bar-shaped shaft formed by deforming nonmagnetic stainless steel and a magnetic member embedded in a groove formed in the longitudinal direction of the shaft. Yes. Then, the magnetic sensor detects the magnetic pole formed on the magnetic member of the sub-moving guide body to detect the position of the moving block. Thus, when position detection is performed by the magnetic scale body and the magnetic sensor, even if dust enters the gap between the magnetic scale body and the magnetic sensor, the detection accuracy is not lowered, and the effect of being resistant to dirt and dust is obtained. is there.

  On the other hand, some printer apparatuses have a structure in which a slider mounted with a print head is moved along a guide rod. The position control of such a print head is controlled by, for example, the amount of movement of a timing belt that drives the slider. ing. Even in such a case, it is desirable that the direct position can be detected by the magnetic scale body and the magnetic sensor, and there is an effect of being resistant to dirt and dust.

In addition, some watch the amount of suspension of motorcycles (motorcycles) and four-wheeled vehicles, and control them to reduce shaking. Even in such a case, it is desirable that the amount of movement can be detected by the magnetic scale body and the magnetic sensor, and there is an effect that it is particularly resistant to dirt such as mud and dust.
Japanese Patent No. 2748166

  By the way, when the moving guide body that holds the moving block is a magnetic scale body, it may be considered that the entire moving guide body is made of a permanent magnet material, but the alloy system is expensive and the ferrite system is brittle and durable. There is a problem in terms of. On the other hand, as proposed by the present applicant, when the moving guide body is mainly composed of a non-magnetic stainless steel shaft having a substantially round bar shape, it is excellent in terms of durability as a guide body.

  However, in the above technique, since the magnetic member is embedded in the groove formed in the longitudinal direction of the shaft of the nonmagnetic stainless steel to constitute the moving guide body, a part of the magnetic member is peeled off from the shaft after many years of use. There is also a possibility that there is still room for improvement in terms of durability as a magnetic scale body.

  It is an object of the present invention to provide a highly durable magnetic scale body that can withstand use not only as a guide body but also in a poor environment.

First, a magnetic scale body manufacturing method according to a reference example is a double pipe body that is nested with an inner pipe body inside an outer pipe body, and the inner pipe body is an inner pipe having a recessed portion around the periphery. The body and the outer tube outside the inner tube form a nested double tube, and the center of the double tube is filled with a rigid powder having high rigidity and hardly magnetism. The recessed part between the outer tube body is filled with magnetic powder, and then the inner tube body is detached. Then, the remaining complex from which the inner tubular body is detached is heated and solidified, the heat-solidified complex is elongated into a rod-shaped body, the outer tubular body is peeled from the elongated rod-shaped body, and the outer tubular body is peeled off. The magnetic part formed by heating and solidifying the magnetic powder was scale magnetized. Note that “hard magnetism” includes “non-magnetic”.

  Therefore, the rigid shaft portion obtained by heat-solidifying the rigid powder and the magnetic material portion obtained by heat-solidifying the magnetic powder are joined together at the joint (joint surface), and can withstand vibration and high temperatures sufficiently like a bimetal. It does not peel off easily. Moreover, the magnetic scale body can be made into a small structure with high accuracy by forming the pipe body with a large diameter size and extending it by rolling or the like.

The magnetic scale body according to claim 1 is provided with a long rigid shaft portion having high rigidity and non-magnetism including non-magnetism, and a layered uniformly and integrally in a longitudinal direction of the rigid shaft portion. A magnetic scale body is formed from the magnetic body portion, and the magnetic body portion is smaller than the rigid shaft portion and is fixed to a part of the surface and magnetized by scale magnetization in the cross-sectional area perpendicular to the longitudinal direction. The joint surface CF (FIG. 5 (B), FIG. 7 (B)) to the rigid shaft portion on both sides in the circumferential direction of the right-angled cross section of the longitudinal direction is the center line between the joint surfaces on both sides with respect to the surface. An undercut structure was adopted in the inner and outer directions parallel to L (FIGS. 5B and 7B). Therefore, the magnetic body portion has a structure that is extremely difficult to peel off against the force in the direction of the center line. The rigid shaft portion in claim 8 can be made of, for example, a nonmagnetic metal, a resin, or the like.

The magnetic scale body according to claim 2 is a long rigid shaft portion having high rigidity and high magnetic permeability, and a magnetic body portion that is uniformly and integrally disposed in the longitudinal direction of the rigid shaft portion. In the same manner as in the eighth aspect, the joint surface CF (FIG. 5B, FIG. 7) to the rigid shaft portion on both sides in the circumferential direction of the cross section in the longitudinal direction of the magnetic body portion. (B)) has an undercut structure in the inner and outer directions parallel to the center line L (FIGS. 5B and 7B) between the joint surfaces on both sides with respect to the surface. The rigid shaft portion in claim 9 can be a resin mixed with a paramagnetic metal, a ferromagnetic metal, a high magnetic permeability material, or the like.

A magnetic scale body according to a third aspect is the magnetic body according to the first or second aspect, wherein the magnetic body portion is a magnetic body for an alloy-based permanent magnet.

A magnetic scale body according to a fourth aspect is the magnetic scale body according to the first or second aspect, wherein the magnetic body portion is an alloy of copper nickel iron.

A magnetic scale body according to a fifth aspect is the magnetic scale body according to the first aspect, wherein the rigid shaft portion is formed of a metal or a high-strength resin, the magnetic body portion is a resin mixed magnet, and the magnetic body portion is inserted into the rigid shaft portion. Molded to form.

A magnetic scale body according to a sixth aspect is the magnetic scale body according to the second aspect, wherein the rigid shaft portion is formed of a high-strength resin mixed with a metal or a high permeability material, the magnetic body portion is a resin mixed magnet, and the rigid shaft portion is The magnetic part was formed by insert molding.

According to claim 5 or 6, the rigid shaft portion as a withdrawal member of metal or high-strength resin, can be inexpensive rigid shaft portion, injection molding a resin mixture magnet (plastic magnet, etc.) to the rigid shaft portion Can be easily formed.

A magnetic scale body according to a seventh aspect is the magnetic scale body according to the fifth or sixth aspect, wherein the rigid body shaft portion is made of high-strength resin, the magnetic body portion is primary molded, and the rigid body shaft portion is secondarily molded with respect to the magnetic body portion. . That is, the rigid shaft portion and the magnetic body portion were formed by two-color molding.

Magnetic scale body according to claim 8, in any one of claims 1 to 7, and the layered thickness of the magnetic body and 0.1 mm to 1 mm.

According to the magnetic scale body of claims 1 to 8 , since the magnetic body portion has a structure that is extremely difficult to peel off against the force in the direction of the center line, the magnetic scale body is highly durable and can withstand use in a poor environment. Become a body.

According to the magnetic scale bodies of claims 3 , 4 , 6, and 7 having the configuration of claim 2 , claim 2 , 6, and 7 , in addition to the above effect, the rigid shaft portion that covers the magnetic body portion has high magnetic permeability, With the rigid shaft portion, a magnetic shield effect for shielding a magnetic field outside the magnetic scale body from the magnetic body portion is obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the oblique line which shows a cross section in drawing is abbreviate | omitted suitably. FIG. 1 is a diagram showing a manufacturing process of a magnetic scale body of a reference example , and each process is indicated by [1], [2],. Examples of dimensions and materials will be described in detail after the description of the process.

  The process [1] is a process (first step) for preparing the nested double tube body 1. The double tube 1 includes an inner tube 11 and an outer tube 12, and the inner tube 11 is accommodated in the outer tube 12. The inner tube 11 has a substantially circular shape obtained by rounding a thin plate-like member having both ends opened, and is formed in a shape having a recess 11a that forms a groove parallel to the cylindrical generatrix at a part of the periphery. The outer tubular body 12 is formed in a cylindrical shape having a bottom at the lower end by a thin plate-like member. In the drawing, the gap d (clearance) between the outer peripheral edge of the inner tube 11 and the inner peripheral edge of the outer tube 12 is exaggerated and illustrated. However, the gap d connects the inner tube 11 to the outer tube. 12 is a minute interval so that it can be detached from 12. In addition, in the drawing, a part of the double tube 1 is omitted by a broken line (two-dot chain line), but the double tube 1 has an appropriate length defined in relation to the diameter (thickness). .

  The inner tubular body 11 is formed by recessing a part of the periphery with the concave portion 11a, and the distance D from the inner wall of the outer tubular body 12 to the outer wall of the inner tubular body 11 is the other peripheral portion of the inner tubular body 11 (other than the concave portion 11a). It is a tube that is larger than Further, the inner tube body 11 and the outer tube body 12 form a double tube body 1 having a nested structure.

  The inner tube 11 may be made of metal, plastic, or the like, for example, a thin one of about 0.5 mm to 2 mm. The outer tubular body 12 is made of a metal material such as stainless steel, copper, or aluminum, and is preferably as thin as about 0.1 to 0.8 mm in consideration of a peeling process described later. Further, the sizes of the inner tube body 11 and the outer tube body 12 may be appropriately determined depending on the diameter and the lot when it is expanded by an extrusion process or a rolling process, which will be described later, and the final product, but the diameter is about 10 mm to 100 mm. It is.

  Step [2] is a step (second step) in which a rigid powder P1 having high rigidity and difficulty in magnetism is filled in the center side (inside the inner tube 11) of the double tube 1 having a nested structure. 3] is a step (third step) of filling the magnetic powder P2 in the concave portion 11a between the inner tube body 11 and the outer tube body 12. The filling work of the rigid powder P1 and the magnetic powder P2 may be manual work or mechanical work, and the filling process of the process [2] and the process [3] may be performed first, but the inner tube 11 In the case where the thin plate member is particularly thin, it is better to perform the step [2] first in order to prevent the inner tube body 11 from being deformed. Further, the order of the process [2], the process [1], and the process [3] may be performed as follows. In this case, both ends of the outer tubular body 12 are opened, the inner tubular body 11 is placed on a large bottom plate or the like, and the rigid powder P1 is filled into the inner tubular body 11 (step [2]). Next, the outer tube 12 is fitted outside the inner tube 11 (step [1]). And the magnetic body powder P2 is filled into the recessed part 11a between the inner side pipe body 11 and the outer side pipe body 12 (process [3]). Then, it progresses to process [4] and subsequent steps.

  Step [4] is a step of detaching (pulling out) the inner tube 11 from the outer tube 12 in the direction of arrow α in a state where the double tube 1 is filled with the rigid powder P1 and the magnetic powder P2. Fourth step). Since both ends of the inner tube 11 are open, the inner tube 11 passes between the rigid powder P1 and the magnetic powder P2 in the recess 11a, and the rigid powder P1 and the outer tube in a portion other than the recess 11a. It passes through between the inner peripheral surface of the body 11. As a result, a recess having a shape matching the recess 11a of the inner tube 11 is formed in the rigid powder P1, and the magnetic powder P2 is clogged in this recess. In this state, the rigid powder P1 and the magnetic powder P1 are magnetic. The body powder P2 is filled in the outer tubular body 12. The integrated body of the outer tube 12, the rigid powder P1, and the magnetic powder P2 in the state after this step [4] is also referred to as “composite filler A” in the following description.

  By removing the inner tube 11, the height (bulk) of the rigid powder P <b> 1 and the magnetic powder P <b> 2 is slightly reduced by the volume of the thin plate member of the inner tube 11, but the rigid powder The height of P1 is reduced by the larger area that was in contact with the inner tube 11. Therefore, the heights of the rigid powder P1 and the magnetic powder P2 in the outer tubular body 12 after the inner tubular body 11 is detached by appropriately setting the filling amount in the steps [2] and [3]. Make the same. Needless to say, the inner tube 11 should be as thin as possible if it has a certain degree of rigidity.

  The next step is a step of performing various types of processing on the composite filler A obtained in step [4]. The first method of pretreatment step [5-1] → step [5] → step [6] (Cold isostatic pressing & hot extrusion method) and the second method of process [5 ']-> step [6']-> post-treatment step [6'-1] (hot isostatic pressing & forging method) There are two methods, but either method may be used.

  The pretreatment [5-1] of the first method is a “cold isostatic pressing process step”, in which the composite filler A is immersed in water in a sealed container, and the composite filler A is equalized by the water pressure in the sealed container. Apply appropriate pressure. Thus, the rigid powder P1 and the magnetic powder P2 of the composite filler A are hardened. The next step [5] is a “billet heating step”, in which the composite filler A that has undergone the pretreatment [5-1] is heated to a predetermined quenching temperature of about 1100 ° C. in an electric furnace (fifth step). Thereby, the composite filler A is heated and solidified to form a billet A ′ in a solid solution state (in this example, a round billet). The next step [6] is a “hot extrusion step”, in which a billet A ′ in a solid solution state is subjected to a hot extrusion process to obtain a rod-like wire member B having a reduced diameter and a predetermined diameter ( (6th step).

  Step [5 ′] of the second method is a “hot isostatic pressing step” in which the composite filler A is pressurized in a pressure heating furnace and heated to a predetermined quenching temperature of about 1100 ° C. Thereby, the composite filler A is heated and solidified to form a billet A ′ in a solid solution state (fifth step). The next step [6 ′] is a “forging step”, in which the diameter is reduced to some extent by pressure forming the billet A ′ in a solid solution state (sixth step). The next post-treatment step [6′-1] is a “rolling treatment step”, in which the pressure-formed billet A ′ is rolled into a rod-like wire member B having a predetermined diameter and a reduced diameter. This rolling process may be repeated a plurality of times.

  The rod-shaped wire member B formed with a predetermined diameter as described above is wound up by the roller 40. The rod-shaped wire member B is wound around the roller 40 from the “hot extrusion step” in the step [6] of the first method or the “rolling step” in the post-treatment step [6′-1] of the second method. In the meantime, the rod-shaped wire member B is set to a temperature between a predetermined annealing temperature of several hundred degrees Celsius and a tempering temperature.

  On the surface of the rod-shaped wire member B wound around the roller 40, a thin plate-like member that has formed the outer tubular body 12 is attached in a stretched state. Therefore, the outer tubular body 12 is peeled off in the “peeling step” of step [7] (seventh step). As shown in FIG. 2 (A), the peeling process includes a peeling jig 51 between the process [6] or the post-processing process [6'-1] and the winding process with the roller 40. May be provided (seventh step). The peeling jig 51 is composed of mesh members 51a and 51b sandwiching the upper and lower sides of the rod-like wire member B that has been subjected to the extrusion process or the rolling process. The distance between the process [6] or the post-processing process [6′-1] and the roller 40 is 1 to 2 m, and the mesh members 51a and 51b are formed on the surface of the rod-shaped wire member B over a length of about 50 to 80% of the distance. The mesh members 51a and 51b scrape off the outer tubular body 12 by friction and peel off. Further, in the peeling process, the outer tubular body 12 may be peeled from the rod-like wire member B by drawing with the dies 51c and 51d as shown in the process [7 ″] shown in FIG.

  In addition, you may make it peel with a friction member like a sheet file instead of or together with the mesh members 51a and 51b. Further, when the outer tube 12 cannot be peeled in one “peeling step”, the “peeling step” may be repeated a plurality of times. If the outer tubular body 12 is still insufficiently peeled, the long rod-like body C before the magnetizing process described later may be finished with a sheet file or the like.

  The rod-shaped wire member B from which the outer tubular body 12 has been peeled off as described above is composed of the rigid body shaft portion C1 obtained by solidifying the rigid body powder P1 by heating and the magnetic body portion C2 obtained by heat solidifying the magnetic body powder P2. In order to obtain the magnetic characteristics (width of the hysteresis magnetization curve) of the magnetic part C2 at an appropriate condition and at an appropriate stage according to the material of the magnetic part C2 (magnetic powder P2) after the “peeling step”. The heat treatment process is performed.

  When the magnetic part C2 is CuNiFe-based, heat treatment is performed after the “peeling step” of this step [7]. For example, the peeled rod-shaped wire member B is subjected to a cold drawing process, and a primary aging process is performed in an atmosphere of 600 to 700 ° C. in argon gas or hydrogen gas for 2 hours. Thereby, a magnetic characteristic is generated in the magnetic part C2. Next, a secondary aging treatment is performed under the same atmospheric conditions to improve the magnetic properties. The magnetic characteristics, that is, the hysteresis magnetization curve can be controlled by the processing rate, the aging temperature, and the time condition between the primary aging treatment and the secondary aging treatment. And when this heat processing is complete | finished, a linear process is performed to the rod-shaped wire member B, and it progresses to the cutting process of process [7-1].

  In the cutting process of the process [7-1], for example, the rod-shaped wire member B drawn from the roller 40 is fed by the extrusion roller 61, cut to a predetermined length by the fixed blade 62 and the vertical moving blade 63, and the long product of the semi-finished product Let it be a rod-like body C. Here, as shown in FIG. 3 (A), the long rod-shaped body C is composed of a rigid shaft portion C1 in which the rigid powder P1 is solidified by heating and a magnetic portion C2 in which the magnetic powder P2 is solidified by heating. The joint portion (joint surface) between the rigid shaft portion C1 and the magnetic body portion C2 is bonded at the time of heat solidification. This “bonding” refers to a state where it can withstand vibrations and high temperatures (below the quenching temperature) and cannot be easily peeled off, like bimetal.

  When the magnetic part C2 is FeCrCo-based, a cold drawing process is performed before this cutting process, a homogenization process such as a solution treatment for 5 minutes in an atmosphere of 1020 ° C. in an argon gas, and skin pass rolling. Processing (temper rolling with a light rolling rate) is performed, linear processing is performed, and the same cut processing is performed. Then, at the stage after this cutting process, an aging process is performed in an atmosphere corresponding to the specified temperature pattern, and a heat treatment process is performed to obtain the magnetic characteristics of the magnetic part C2. When the cutting process or the heat treatment in this case is completed, centerless polishing (a method of polishing the surface close to a perfect circle without defining the center) for polishing the surface of the long rod-shaped body C is performed.

  Next, in FIG. 1, step [8] is a “magnetization step” (eighth step), and the magnetizing device 70 is used. The magnetizing device 70 is composed of a large number of needles 71 erected over the length of the long rod-like body C and a circuit device 72 that forms magnetic poles on the needles 71. The needles 71 are in contact with the magnetic part C2 of the long rod-like body C, and the N poles and the S poles are alternately formed between the adjacent needles 71 on the many needles 71. Thereby, the magnetic part C2 is formed with magnetic poles in which the N pole and the S pole are alternately and finely polarized (for example, in a cycle of 400 μm) in the longitudinal direction. The state of the magnetic pole is shown by a number of fine lines in FIG. In this manner, the magnetic scale body 10 is obtained by magnetizing the NS pole in the longitudinal direction on the magnetic part C2 of the long rod-like body C, that is, by being scale-magnetized. In the magnetic scale body 10, the rigid body shaft portion C1 is referred to as a shaft portion 10a, and the scale-magnetized magnetic body portion C2 is referred to as a scale portion 10b.

  The magnetizing step may be as shown in FIG. In this case, a magnetizing device 70 'composed of two needles 71' and 71 'and a coil 72' is used. While the needles 71 'and 71' are in contact with the magnetic part C2 of the long rod-shaped body C, an alternating current is supplied to the coil 72 'to reverse the magnetic field between the needles 71' and 71 ', while the long rod-shaped body C May be moved at a constant speed. In this case, the NS pole cycle can be set according to the AC frequency and the moving speed.

  In the manufacturing process of the magnetic scale body 10 described above, as a process for extending the heat-solidified billet A ′, hot extrusion is performed in the step [6] of the first method (cold isostatic pressing & hot extrusion method). The rolling process is performed in the post-processing step [6′-1] of the second method (hot isostatic pressing & forging method). However, this extending process may combine these steps. For example, the billet A ′ may be stretched by passing through an extrusion process, a rolling process, and a drawing process in order with respect to the billet A ′ that has been heat-solidified, and processing the permutations of the respective processing units simultaneously.

  The rigid powder P1 is made of stainless steel (SUS), brass, duralumin, or a ceramic material, and is a material that is hard to rust, has rigidity, and is hard to be magnetized. For example, as the stainless steel, nickel-chromium-based 8% Ni18% Cr, 18Cr-8Ni austenitic system developed from this 8% Ni18% Cr, etc. are excellent as non-magnetic steel.

The magnetic powder P2 is a permanent magnet material or the like. This permanent magnet material includes an alloy system such as Fe-Cr-Co system, Fe-Cu-Ni system, Mn-AL-C system, and Nd-Fe system. Examples of the compound system include RE-Co system (Sm ₂ Co ₁₇ system is representative). Of these, the Fe—Cr—Co system is suitable for cold rolling, and drawing is particularly possible. Examples of oxides include y-Fe ₂ O ₃ , Fe304 (magnetite), MO · Fe ₂ O ₃ (ferrite, M is a divalent metal ion such as Mn, Ni, Cu, Zn, Ba). When using difficult-to-process magnet material powder, use metal powder for binder.

  Also, the rigid powder P1 and the magnetic powder P2 are suitably spherical metal powders manufactured by vacuum melting and gas atomization method, and the particle diameter is a predetermined particle diameter divided by a sieve of about 30 to 300 μm. . When such a spherical metal powder is used, the packing density increases, and dimensional deformation after heat solidification can be suppressed.

  Next, the shape of the magnetic part C2 (and the rigid shaft part C1) of the long rod-like body C will be described. The outer shape of the long rod-like body C becomes a columnar shape due to the cylindrical shape of the outer tubular body 12, but the shape of the magnetic part C <b> 2 is determined by the shape of the concave portion 11 a of the inner tubular body 11. 4 and 5 are views showing the shape of the inner tubular body 11 of the double tubular body 1 and the cross section of the long rod-like body C manufactured using the same, and the thickness of the thin plate member of each tubular body. The depth of the recess 11a is exaggerated.

  FIG. 4A shows a shape in which the bottom surface 111 of the concave portion 11a of the inner tube body 11 has a concave arc surface concentric with the outer circular arc surface of the outer tube body 12, and the side surfaces 112, 112 on both sides are made parallel to each other. Shape. In this case, as shown in FIG. 4B, the cross-sectional shape of the magnetic part C2 is an arc. 5 (A) shows a shape in which the bottom surface 111 of the recess 11a of the inner tube 11 has a concave arc surface concentric with the outer peripheral arc surface of the outer tube 12, and the side surfaces 112, 112 on both sides face inward. Open shape. Also in this case, the cross-sectional shape of the magnetic part C2 is an arc as shown in FIG. 5B, but the shape on both sides of the magnetic part C2 is different from the case of FIG. 4B. When this long rod-like body C is applied to a slide volume device to be described later, the diameter φ of the rigid shaft portion C1 is about 4 mm, and the thickness D of the magnetic body portion C2 is about 0.15 mm. In addition, if the recessed part 11a is the shape dented in the center side of the inner side pipe body 11, it will not be limited to said example.

  Here, in the inner tube body 11 of FIGS. 4A and 5A, the inner corner S1 of the recess 11a has a double tube as shown in FIGS. 6A and 6B in an enlarged manner. It has an undercut structure with respect to the direction of the normal line n of the outer peripheral surface which is the inner and outer direction of the body 1. This undercut structure has the following meaning. That is, in the case of an undercut structure as shown in FIGS. 6 (A) and 6 (B), the inner corner S1 and the outer space SO of the double tubular body 1 on the normal line n (extension line thereof). There is a space S2 at the outer peripheral end of the inner tubular body 11 between them. On the other hand, when the undercut structure is not used as shown in FIG. 6 (C), the space S2 at the outer peripheral end of the inner tube 11 is formed on the normal line n with the inner corner S1 and the double tube. It is not between the outer space SO of the body 1.

  FIGS. 6D to 6F are views showing a cross section of the long rod-shaped body C corresponding to FIGS. 6A to 6C. First, the structure of the long rod-shaped body C is as follows. ing. The rigid shaft portion C1 has high rigidity and hardly magnetism, and the magnetic body portion C2 is uniformly and integrally disposed in the longitudinal direction (direction perpendicular to FIG. 6) of the rigid shaft portion C1. Furthermore, the ratio of the cross-sectional area perpendicular to the longitudinal direction of the magnetic part C2 and the cross-sectional area perpendicular to the longitudinal direction of the rigid shaft part C1 is smaller in the magnetic part C2 than in the rigid shaft part C1. Further, the magnetic part C2 is fixed to a part of the surface of the rigid shaft part C1.

  The same thing as the undercut structure in the double tubular body 1 shown in FIGS. 6A to 6C can be applied to the shape of the magnetic body portion C2 (and the rigid shaft portion C1) of the long rod-like body C. That is, FIGS. 6D and 6E show the case of the undercut structure, and the rigid axis is formed between the corner C21 of the magnetic part C2 and the outer space SO of the long rod-like body C on the normal line n. There is an outer peripheral end C11 of the part C1. FIG. 6F shows a case where the undercut structure is not employed, and the outer peripheral end C11 of the rigid shaft portion C1 is formed between the corner portion C21 of the magnetic body portion C2 and the outer space SO of the long rod-like body C on the normal line n. Not in between.

  6 (D) and 6 (E), when the undercut structure is employed, the magnetic body portion C2 is joined at the joint between the magnetic body portion C2 and the rigid shaft portion C1 on the outer periphery of the long rod-like body C. The angle θ becomes an obtuse angle. Therefore, even when rubbed in the direction indicated by the arrow β, the end of the magnetic part C2 is extremely difficult to peel off. In the case of FIG. 4B (and FIG. 6D), the joint surfaces CF and CF (joint surfaces on both sides) with the rigid shaft portion C1 on both sides of the magnetic body portion C2 are parallel to each other. It is not an undercut structure with respect to the direction of the center line L (center line between the joint surfaces CF and CF). However, in the case of FIG. 5B (and FIG. 6E), the joint surfaces CF and CF (joint surfaces on both sides) are center lines L (joint surfaces) with respect to the surface of the long rod-like body C. It has an undercut structure with respect to the inner and outer directions parallel to the center line between them. Therefore, in the case of FIG. 5B (and FIG. 6E), the structure is extremely difficult to peel off with respect to the force in the direction of the arrow γ.

  According to the manufacturing method of the magnetic scale body described above, the double tube body 1 is extruded with respect to a large composite filler A (and billet A ′) formed by filling the rigid powder P1 and the magnetic powder P2. Since the elongation process is performed by the process, the rolling process, the drawing process, and the like, the tube can be formed in a large size, and the magnetic scale body 10 can be made into a small structure with high accuracy according to the purpose. Further, the diameter (size) of the magnetic scale body 10 can be made finer and finely adjusted.

  Next, another embodiment of the magnetic scale body will be described. FIG. 7 is a perspective view and a cross-sectional view taken along line AA of the magnetic scale body 20 of another embodiment. The magnetic scale body 20 includes a shaft portion 20a as a “rigid shaft portion” and a scale portion 20b as a “magnetic body portion”. The shaft portion 20a is formed by drawing nonmagnetic stainless steel (18Cr-8Ni austenite), which is a nonmagnetic metal, and has a groove portion 20a1 in its longitudinal direction. The scale portion 20b is a plastic magnet obtained by mixing and kneading ferrite powder, which is magnetic powder, and plastic, which is a thermoplastic resin. The scale portion 20b and the shaft portion 20a are integrally formed by insert-molding the plastic magnet into the groove portion 20a1 of the shaft portion 20a.

  That is, the structure of the magnetic scale body 20 is as follows. The shaft portion 20a has high rigidity and hardly magnetism, and the scale portion 20b is uniformly and integrally arranged in the longitudinal direction of the shaft portion 20a. Furthermore, the ratio of the cross-sectional area perpendicular to the longitudinal direction of the scale portion 20b and the cross-sectional area perpendicular to the longitudinal direction of the shaft portion 20a is smaller in the scale portion 20b than in the shaft portion 20a. The scale portion 20b is fixed to a part of the surface of the shaft portion 20a.

  The same thing as the undercut structure in FIGS. 6 (D) and 6 (E) can be applied to the shape of the scale portion 20b (and shaft portion 20a) of the magnetic scale body 20. That is, as shown in FIG. 7B, the outer peripheral end portion 20a2 of the shaft portion 20a exists between the corner portion 20b1 of the scale portion 20b and the outer space SO of the magnetic scale body 20 on the normal line n. Further, the joint surfaces CF and CF (joint surfaces on both sides) with the shaft portions 20 a on both sides of the scale portion 20 b are parallel to the center line L (center line between the joint surfaces) with respect to the surface of the magnetic scale body 20. It has an undercut structure for the inner and outer directions. Therefore, the scale portion 20b has a structure that is extremely difficult to peel off against the force in the direction of the arrow γ.

In the above example, the shaft portion 20a as the “rigid shaft portion” is made of non-magnetic stainless steel, but may be made of brass, duralumin, or a ceramic material, and is hard to be rusted, rigid, and hard to be magnetized. Further, in the scale portion 20b as the “magnetic body portion”, ferrite powder is used as the magnetic body powder mixed in the plastic magnet. As this magnetic body powder, Fe—Cr—Co, Fe—Cu—Ni, Mn-AL-C, Nd-Fe, etc. may be used. Further, the RE-Co system (Sm ₂ Co ₁₇ system is typical) may be used as the compound system. Further, y-Fe ₂ O ₃ and Fe304 (magnetite) may be used as the oxide system. When using difficult-to-process magnet material powder, use metal powder for binder.

  In the above example, the shaft portion 20a as the “rigid shaft portion” is formed of a nonmagnetic metal. However, the shaft portion 20a is formed by drawing a hard resin, and the shaft made of the hard resin. The scale part 20b may be formed by insert molding a plastic magnet in the groove part 20a1 of the part 20a. Alternatively, the scale portion 20b may be primarily molded with a plastic magnet, the shaft portion 20a of hard resin may be secondarily molded thereon, and the magnetic scale body 20 may be formed by two-color molding of the resin.

  The shaft portion 20a may be formed of a metal having a high magnetic permeability, or may be formed by mixing a member having a high magnetic permeability with a hard resin. In this case, since the three surfaces on the outer periphery in the longitudinal direction of the scale portion 20b are covered with the shaft portion 20a having a high magnetic permeability, such a magnetic scale body 20 can obtain the effect of a magnetic shield for shielding an external magnetic field.

  In addition, the size of each part of the magnetic scale body 20 of this embodiment can be set in various ways depending on the application. For example, it can be the same as that of the magnetic scale body 10 of the above embodiment.

  Next, the use of the magnetic scale bodies 10 and 20 of the embodiment will be described. In addition, although a magnetic scale body differs in size etc. according to a use, hereafter, a magnetic scale body is demonstrated as the same code | symbol "10". FIG. 8 is a perspective view of a main part of a slide volume device using the magnetic scale body 10 of the embodiment. This slide volume device is mounted on a mixer device, and includes a side plate 21A that forms a right-angle plane on the back side of the console panel surface 100 of the mixer device, and a side plate that is paired with the side plate 21A on the front side (see FIG. (Not shown) and an upper frame 21U having a U-shaped cross section constitute a frame. A motor 22 is attached to one end of the upper frame 21U. Further, claws 23, 23, 24, 24 are raised by bending at both ends of the side plate 21 A, and the magnetic scale body 10 as a moving guide is interposed between the claws 23, 23 between the claws 24, 24. A moving guide body 25 is attached.

  A moving block 31 is attached to the magnetic scale body 10 and the sub movement guide body 25 so as to be slidable in the longitudinal direction of the magnetic scale body 10 and the sub movement guide body 25. The moving block 31 is provided with a lever 36 for inserting an operator not shown. The motor 22 reciprocates the moving block 31 in order to automatically set the position of the slide operation element of the slide volume device.

  The moving block 31 is resin-molded, and the guide holes 32 and 32 into which the magnetic scale body 10 is inserted into the upper side of the square-shaped frame, and the sub guide into which the sub moving guide body 25 is inserted into the lower side. Holes 33 are respectively formed. A substrate 34 is attached to the inside of the frame, and a magnetic sensor 35 is attached to the substrate 34. A flat cable 36 that outputs a signal from the magnetic sensor 35 is connected to the substrate 34.

  The magnetic scale body 10 scales and magnetizes the shaft portion 10a composed of the rigid shaft portion C1 of nonmagnetic stainless steel (18Cr-8Ni austenite system) and the magnetic body portion C2 of a permanent magnet material (Fe—Cr—Co system). And the scale portion 10b formed. As described above, the scale portion 10b is formed with magnetic poles by alternately polarizing the N pole and the S pole in the longitudinal direction at a period (pitch) of 330 μm, for example. A type sensor 35 is arranged oppositely. The magnetic sensor 35 includes two magnetoresistive elements (MR elements). When the moving block 31 moves along the magnetic scale body 10 and the sub moving guide body 25, the magnetic sensor 35 uses the magnetic pole of the scale portion 10b. Sense and output a signal. The detection signal of the magnetic sensor 35 is sent to a circuit (not shown) via the flat cable 36.

  Here, as the moving block 31 moves, the magnetic sensor 35 outputs a pulse signal corresponding to the reversal of the polarity of the N pole and the S pole of the scale unit 10b. The moving amount (length) of the moving block 31 can be detected from the number of pulse signals. Further, the magnetic poles of the scale portion 10b are composed of, for example, two rows, and the pattern of the magnetic poles is shifted in phase by 1 / 2π in the longitudinal direction of the magnetic scale body 10, and the magnetic sensor 35 outputs a pulse signal having a phase shift. Since the data is output, the moving direction of the moving block 31 is determined by the direction opposite to the phase shift. The magnetic pole pattern of the scale portion 10b is composed of an NSNS... Pattern having no phase shift, and the detection pole portion of the sensor may be arranged with a shift of 1 / 2π.

  FIG. 9 is a perspective view of an essential part of a suspension part of an automobile using the magnetic scale body 10 of the embodiment. The impact of the vertical movement of the wheel 81 attached to the car body 80 of the automobile is buffered by the suspension 82. The magnetic scale body 10 of the embodiment is used as the main shaft of the suspension 82. As illustrated in the two-dot chain line blowing portion in the figure, the magnetic scale body 10 includes a shaft portion 10a of nonmagnetic stainless steel (18Cr-8Ni austenite system) and a permanent magnet material (Fe—Cr—Co) as described above. System) scale unit 10b. In addition, the magnetic poles are alternately formed in the longitudinal direction of the scale portion 10b in the longitudinal direction, as in the above case.

  A spring bearing shaft 84 that receives one end of the spring 83 of the suspension 82 is fixed to the magnetic scale body 10. The magnetic scale body 10 is slidably held by a receiving shaft 85 having a fixed relationship with the vehicle body 80, and the other end of the spring 83 is in contact with a spring stopper 86 attached to the receiving shaft 85. A magnetic sensor 91 is embedded in the receiving shaft 85 with a screw or the like, and this magnetic sensor 91 is opposed to the scale portion 10b. Based on the detection signal of the magnetic sensor 91, the vertical movement of the magnetic scale body 10 relative to the receiving shaft 85, that is, the vertical movement of the main shaft is detected, and traveling control can be performed based on the detection result.

  As another embodiment, although not shown or omitted, the magnetic scale body 10 can also be applied to a sliding shaft that slidably holds a print head holding portion of a printer apparatus. In this case, a magnetic sensor is attached to the head holding portion that holds the print head, and the magnetic sensor senses the magnetic pole of the scale portion 10b of the magnetic scale body 10 (sliding shaft), thereby detecting the position of the head holding portion, that is, the print head. The position can be detected.

  As described above, the magnetic scale body according to the present invention is suitable for use in a place that frequently slides (moves), such as a slide volume device, a suspension unit, or a printer device, that is, a place that is overused. . Even in such a case, not only the shaft portion 10a (the rigid shaft portion C1) of the magnetic scale body 10 but also the scale portion 10b (the magnetic body portion C2) is made robust, so that the moving portion (for example, the moving block 31 or the head holding member). As a guide body (or a sliding shaft) for the portion) and a main shaft for the fixed portion (for example, the receiving shaft 85), it exhibits high durability and is extremely suitable. In particular, it can withstand use in a poor environment, such as an automobile suspension.

  FIG. 10 is a diagram showing another embodiment of the magnetic scale body. A magnetic scale body 10 'shown in FIG. 10A has a shaft portion 10a' (and a scale portion 10b ') formed in an arc shape. In order to form such a magnetic scale body 10 ', the double tube described in FIG. 1 may be shaped so that the central axis is an arc, and the central axis is an arc. The inner tube can also be pulled out along the arc. In this magnetic scale body 10 'as well, the magnetic pole of the scale portion 10b' has the NS pole magnetized in the axial direction as in FIG. 3B, and the position and / or movement amount in the direction along the arc by the magnetic sensor. Can be detected.

  The magnetic scale body 10 ″ shown in FIG. 10B is obtained by forming a scale portion 10b ″ spirally wound around the linear shaft portion 10a ″. Such a magnetic scale body 10 ″. In order to form the inner tube 11, the inner tube 11 may be pulled out while being twisted with respect to the outer tube 12 in the step [6] described with reference to FIG. This is also an advantage of being filled with powder in the double tube 1, but the recess 11 a of the inner tube 11 is formed in a spiral shape and twisted along the spiral. You may make it pull out. In the scale portion 10b ″ of the magnetic scale body 10 ″, the NS pole is scale-magnetized in the circumferential direction as shown in FIG. 10C, for example.

  The magnetic scale body 10 ″ moves relative to each other so that the magnetic sensor 91 ″ is along the scale portion 10b ″ (so as not to be detached from the scale portion 10b ″) in the positional relationship with the magnetic sensor 91 ″. For example, when the magnetic sensor 91 ″ is fixed, the magnetic scale body 10 ″ moves linearly while rotating, and its twist position and / or twist amount can be detected. Can detect the torsion position directly. For example, if the NS pole is magnetized in the axial direction as in FIG. 3B, the amount of movement in the axial direction and the amount of twist (angle) are proportional to each other. Therefore, the twist position can be detected from the position in the axial direction.

  In the embodiment, the case where the double tube body, the inner tube body, and the outer tube body have a cylindrical shape and the long rod-shaped body and the magnetic scale body have a columnar shape has been mainly described, but these shapes are perpendicular to the axis. It goes without saying that the cross-sectional shape may be any polygonal shape such as a triangle, a quadrangle, a pentagon, and so on.

  In addition, the magnetic scale body in the present invention is not limited to the slide volume device, the vehicle suspension, and the printer device, and the movement position between a plurality of relatively moving members in various other devices such as a camera autofocus mechanism. And can be used to detect the amount of movement.

It is a figure which shows the manufacturing process of the magnetic scale body manufacturing method of the reference example which concerns on this invention. It is a figure which shows the other example of the peeling process in a reference example . It is a figure which shows the example of magnetization of the elongate rod-shaped body and magnetic scale body in embodiment. It is a figure which shows the cross section of the shape of the double pipe body in embodiment, and the elongate rod-shaped body manufactured. It is a figure which shows the other example of the cross section of the shape of the double tube body in embodiment, and the manufactured elongate rod-shaped body. It is an enlarged view which shows the cross-section of the shape of the recessed part of the double pipe body in embodiment, and a long rod-shaped body. It is the perspective view and sectional drawing which show the other example of the magnetic scale body of embodiment. It is a principal part perspective view of the slide volume apparatus using the magnetic scale body of embodiment. It is a principal part perspective view of the suspension part of the motor vehicle using the magnetic scale body of embodiment. It is a figure which shows the other Example of the magnetic scale body in embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Double tube body, 10, 10 ', 10 ", 20 ... Magnetic scale body, 10a, 20a ... Shaft part (rigid body shaft part), 10b, 20b ... Scale part (magnetic body part), 11 ... Inner pipe body , 11a ... concave portion, 12 ... outer tube body, 25 ... sub moving guide body, 31 ... moving block, 32 ... guide hole, 33 ... sub guide hole, 35, 91, 91 "... magnetic sensor, 80 ... car body, 81 ... wheel, 82 ... suspension, P1 ... rigid powder, P2 ... magnetic powder, A ... composite filler (composite), C ... long rod (bar), C1 rigid shaft, C2 ... magnetic body , CF ... Joint surface, L ... Center line

Claims (8)

A magnetic scale body comprising a long rigid shaft portion having high rigidity and non-magnetism including non-magnetism, and a magnetic body portion uniformly and integrally disposed in the longitudinal direction of the rigid shaft portion. Because
The magnetic body portion is smaller than the rigid shaft portion in comparison with a cross-sectional area perpendicular to the longitudinal direction and is fixed to a part of the surface and is scale-magnetized. A magnetic scale body, wherein a joint surface of the side to the rigid shaft portion has an undercut structure in the inner and outer directions parallel to the center line between the joint surfaces of the two sides with respect to the surface. A magnetic scale body comprising a long rigid shaft portion having high rigidity and high magnetic permeability, and a magnetic body portion that is uniformly and integrally disposed in the longitudinal direction of the rigid shaft portion. ,
The magnetic body portion is smaller than the rigid shaft portion in comparison with a cross-sectional area perpendicular to the longitudinal direction and is fixed to a part of the surface and is scale-magnetized. A magnetic scale body, wherein a joint surface of the side to the rigid shaft portion has an undercut structure in the inner and outer directions parallel to the center line between the joint surfaces of the two sides with respect to the surface. Magnetic scale body according to claim 1 or 2, wherein the magnetic body is characterized by comprising a magnetic alloy based permanent magnet. Magnetic scale body according to claim 1 or 2, wherein the magnetic body is characterized by an alloy of copper-nickel iron. The rigid shaft portion is formed of metal or high-strength resin, the magnetic body portion is a resin mixed magnet, and the magnetic body portion is formed by insert molding the rigid shaft portion. The magnetic scale body according to claim 1 . The rigid shaft portion is formed of a high-strength resin mixed with metal or a high permeability material, the magnetic body portion is a resin mixed magnet, and the magnetic body portion is formed by insert molding the rigid shaft portion. The magnetic scale body according to claim 2 , wherein the magnetic scale body is provided. Wherein a rigid shank said high strength resin, wherein the magnetic body and the primary molding, according to claim 5 or 6, characterized in that the secondary molding of the rigid shaft relative to the magnetic body portion The magnetic scale body described in 1. The magnetic scale body according to any one of claims 1 to 7 , wherein a layer thickness of the magnetic body portion is 0.1 mm to 1 mm.

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